ASP.NET System.FormatException

I have the follwing error:

   Stack Trace:   
at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall)     
at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)     
at DocumentManager.Web.MidasInterface.MIDASCustomerInfo.GetBaseRate(String ccy, String brcod) in D:\2010\RETAIL\DocumentManager.Web\Web References\MidasInterface\Reference.vb:line 696   
...

the inner message:

System.FormatException: Index (zero based) must be greater than or equal to zero and less than the size of the argument list.    
at iMIDAS.MIDASCustomerInfo.GetBaseRate(String ccy, String brcod)    

the web method query in db

<WebMethod()> Public Function GetBaseRate(ByVal ccy As String, ByVal brcod As String) As ResponseObject
        Dim connAS400 As New Data.OleDb.OleDbConnection
        Dim dsAS400 As Data.DataSet
        Dim cmdAS400 As Data.OleDb.OleDbCommand
        Dim retVal As Object
        Try
            connAS400.ConnectionString = CreateConnectionStringMidas(DataSource, DataCatalog, DataUser, DataPassword)
            cmdAS400 = New Data.OleDb.OleDbCommand(CreateSQLBaseRate(ccy, brcod), connAS400)
            connAS400.Open()
            retVal = cmdAS400.ExecuteScalar()
            If IsNothing(retVal) Or IsDBNull(retVal) Then
                oResponse.ResponseState = False
                oResponse.ResponseMessage = String.Format("No Records Found for base rate code [{1}]!", brcod)
            Else
                oResponse.ResponseState = True
                oResponse.ResponseDa开发者_如何学Gota = CType(retVal, String).ToString().ToUpper()
            End If
            Return oResponse
        Catch ex As Exception
            Throw ex
        Finally
            connAS400.Close()
        End Try
    End Function

Any ideas?

I'm pretty sure it's this line:

oResponse.ResponseMessage = String.Format("No Records Found for base rate code [{1}]!", brcod)

which should be zero indexed, not one indexed, so:

oResponse.ResponseMessage = String.Format("No Records Found for base rate code [{0}]!", brcod)